Since 1999, guitarist Billy Howerdel has been one half of the creative force behind A Perfect Circle, along with Tool‘s Maynard James Keenan. He’s also the head honcho of Ashes Divide, an alt-prog band that has a single album to their credit, 2008’s Keep Telling Myself It’s Alright. Over the next few months, fans of both bands will see a flurry of releases.

A Perfect Circle will be issuing a “best-of” compilation called Three Sixty on November 19th, followed by a box set of live material on November 29th called A Perfect Circle Live: Featuring Stone and Echo. Meanwhile, Ashes Divide is planning on releasing a new album early next year. Howerdel recently spoke to Rolling Stone about revisiting A Perfect Circle, the new Ashes Divide material and his days as a Fishbone roadie.

I’d imagine it’s a pretty big career milestone when a band gets their first greatest hits release.It was fun listening back. I did a little piece for some publication, to give a two-minute synopsis of the song and the memories of it, and it forced me to go back and listen to some of these studio recordings, which I really haven’t done much. When you get done recording a song, you pretty much just hear it when you play it live. So hearing it and reflecting upon it was a real nostalgic, semi-tearjerking exercise in thinking back about what transpired to make these songs come about, from the beginning of writing them to getting them recorded and getting them released. So that kind of was a thing that made me feel like this release was really . . . a special thing. [Laughs.]

Let’s talk about “By and Down,” which is included on Three Sixty, and is A Perfect Circle’s first new composition in nine years. It kind of came about in 2010, 2011. The song was unique in that we played it live on the 2011 tour, before it was recorded in the studio, which was kind of interesting for us, because we usually do it the opposite way, where you do a studio recording and try and figure out how you’re going to retool it to play it live. So that song found its legs and where it should be, and I was able to go back in the studio and re-record it. Which wound up being more challenging. I thought you’d just throw it down, but studio recordings are just a different thing than live. It’s a different thing than rehearsal – especially for a band like this, where there are layers and textures involved. So that was a little more challenging than I thought.

The song started out just plucking around on the keyboard. I was playing around with my three-year-old son at the time, and as he was pounding with both fists on the keyboard, I just happened to come up with a little melody and recorded it quickly, and then revisited it an hour later and got the beginnings of the song laid out. I sent it to Maynard, and he seemed to like it. He put some vocal-scat syllables and rhythm on it, sent it back, and I knew it was going to be a contender for a song. And it just built it from there.

With the box set, how was it listening to the live tracks, and which renditions are your favorites?Well, the box set is the live show, which is Stone and Echo, which we shot at Red Rocks, and it’s over an hour and a half. Of that show, to be honest, I really like the eMOTIVe record reworked in a live sense. That was the most challenging thing that I’ve ever done, trying to figure out how to take these cover songs that we did – some of them were new APC songs that we had started, and then they became covers as soon as you sing someone else’s lyrics on top of it. And sometimes very loosely following the vocal melody. I think it was an interesting record, but it was much more challenging to take these things and make them live, because some of them were more subdued, and they weren’t going to lend themselves to a live setting.

In 2010, we set out to do a selective city tour, one night per our three records – we had to play the whole record in its entirety. And it had to feel in sequence too, from front to back. So we had to rework these things and give it some legs in different places, to have ebbs and flows during the live set. And I think that was a great challenge and made us stretch and grow musically, to do that. Certain things, like “When the Levee Breaks,” I think, was one of my favorites on the record, but certainly a favorite live. What Maynard did with “The Fiddle and the Drum,” just the sparseness of his vocal and a few single piano notes, was a pretty powerful moment during the tour.

How’s the new Ashes Divide record coming along?I’ve been writing it for a while. I’ve realized I was really writing the next APC record when I was writing this Ashes record, and I was struggling with the vocals on it. I think that it just occurred to me about six months ago that this was the case. So just in August of this year, I really started ripping it apart and just writing new songs. I really like the direction the record is going in now. It’s got a freshness to it that I think is the proper second Ashes record. And I hope to have it out in the spring of 2014, and get on the road after that.

How does it compare to the debut, Keep Telling Myself It’s Alright?The first Ashes record, I started it and ended it with more towards the APC sound, stripped away, and so it brought me from and takes me back into APC. And the songs in between are a little more uplifting. I think these in a way are, too. I’m trying to find optimism in the music a little bit more, a little bit more upbeat. But there’s plenty of places where I go – that’s a big contradiction, because the record is a little bit more mature than the first. I don’t know if the first one was immature. I just know I find this one to be a little bit more serious.

Who plays on the new Ashes Divide album?It will be Jeff Friedl on drums, who’s playing with us in APC currently, and Matt McJunkins, our bass player who played on the APC album, is coming back. Matt and Jeff were the band that I put together for the Ashes tour back in 2008, so they’ll be continuing on. I’ll figure out the rest of the band members from there.

What about future recording plans with APC?I hope to, but I know Maynard is in full Tool mode right now. They’re writing a new record, and I have given him some songs that maybe he’s going to look at, but I don’t know how he does with juggling those things at the same time. I’d like to get an APC record underway. But I don’t know – I’m just leaving it up to him and what his schedule allows. I’ll be there when he’s available.

Something a lot of people don’t seem to know about you – you were Fishbone’s guitar tech back on Lollapalooza 1993.Lollapalooza was awesome to be on as a performer – APC played Lollapalooza – but being a guitar tech on it as well, you’re on this traveling circus. There were so many cool acts. Fishbone was actually on the very first Lollapalooza with Jane’s Addiction [eds. note:Fishbone played a handful of shows on the inaugural Lollapalooza, then played the entire 1993 tour] and Siouxsie and the Banshees. Siouxsie and the Banshees is “top three favorite bands” for me. And all those tours were eclectic in a perfect kind of way, and just had a great vibe. It was kind of the Wild West of these alternative festivals, and taking the nod from all the cool European festivals that had been going on for so long. But certainly, to have that in America was a special moment.

Was Lollapalooza 1993 your first time hearing Tool and meeting Maynard?I saw them at Club Lingerie, this tiny little club on Sunset Boulevard. I was living with one of the guys in Fishbone [guitarist Kendall Jones], and his girlfriend was working at the record company who just signed Tool, so Opiate was just coming out. We went to go see them play, and I just remember seeing Maynard . . . I didn’t know him at the time. It was the first and only time I saw him play without knowing him. I mean, this guy and this Mohawk, wearing this salmon-colored wrestling-pajama-singlet thing, staring at one place on the wall, as he’s singing with the most intensity I’ve ever seen. I was like, “Wow. This is different.”